Heat Strengthened Glass - Test Procedure for Consolidated Glass Corporation

In order to insure that we maintain the highest quality assurance for our heat strengthened glass, the following procedures are to be followed.

1. Test glass of appropriate thickness is to be run prior to any production run and every 45 minutes during the run, until the run is complete.
2. A test piece will also be pulled from the last load that has been run to be tested. So a run taking two hours will have four pieces tested and a run that takes less than 45 minutes will have two pieces tested.
3. In accordance with ASTM 1048 section 11.7.1 the surface compression will be measured by light refraction using a laser GASP.
4. Two surface compression measurements shall be made in each of the five locations, oriented in two directions at 90 degree of each other, for a total of ten readings.

1. The average of the ten readings will be the stress level of the test sample.
2. The stress level will be compared to the chart provided by the manufacturer of the laser GASP.
3. For  6mm ( ¼”) and less shall have a surface compression between 3500 and 7500 psi.
4. The readings will then be registered on Consolidated Glass Corporation’s computer system and kept on file for a period of no less than ten years.
5. Any glass that is out of the specifications shall be isolated up to the point of the last passed test.
6. This glass will be reworked if possible. If not possible to rework it will be destroyed.
7. To insure that the laser GASP is functioning properly, it will be returned to the manufacturer once a year, each year, to insure that it is within calibration.